Variable timing rotary valve for an internal combustion engine

Abstract

A rotary valve with means for effecting variable timing of intake valve opening, variable opening duration and variable timing of closing in response to changes in each engine cylinder's appetite for an intake charge is disclosed. Earliest valve opening, longest duration and latest closing occur when each cylinder's appetite for an intake charge is largest, while latest opening, shortest duration and earliest closing occur when each cylinder's appetite for an intake charge is smallest. Intake valve timing can be varied sufficiently to permit use of the theoretical Top Dead Center Opening and Bottom Dead Center Closing for idle, low speed and coasting operating modes to the typical average 20 degrees Before Top Dead Center Opening 50 degrees After Bottom Dead Center Closing for high speed-high load operating mode.

Having described my invention what I claim as new and desire to secure by Letters Patent is: 
     
       1. Engine apparatus for obtaining variable intake valve timing in an internal combustion engine comprising at least one cylinder said apparatus comprising: A. a support member having at least one port communicating with each cylinder and formed with an interior which is at least partially hollow;   B. a rotatable valve member housed within said support member said valve member having means of support for rotation about an axis, and circumferential intake porting means for uncovering said port in said support member for selectively enabling and preventing the flow of intake charge through the valve and its ducting means into the cylinder;   C. means for driving said rotatable valve member at a precise angular speed in relation to crankshaft speed; and,   D. means mounted for rotation with said rotatable valve member responsive to the difference in the pressure in said rotatable valve member and said cylinder for changing the effective length of said circumferential intake porting means in said rotatable valve said changing of effective length resulting in changing of the timing and duration of effective communication of said circumferential intake port with said support member port during which intake charge flow is permitted.   
     
     
       2. Engine apparatus for obtaining variable timing of opening, variable opening duration and variable timing of closing in a rotary intake valve for internal combustion engines comprising at least one cylinder said apparatus comprising: A. a support member having at least one port communicating with each cylinder and formed with an interior which is at least partially hollow;   B. a rotatable valve member housed within said support member said valve member having means of support for rotation about an axis and a circumferential intake port for uncovering said port in said support member for selectively enabling and preventing the flow of intake charge through the valve and its ducting means into the cylinder;   C. means for defining segments of said circumferential intake port adjacent to the leading and trailing edges of said port through which intake charge may flow; and, means for driving said rotatable valve member at a precise angular speed in relation to crankshaft speed   D. means mounted for rotation with said rotatable valve member responsive to the difference in the pressure in said rotatable valve member and said cylinder for blocking and unblocking said segments of said circumferential intake port adjacent to the leading and trailing edges of said port thereby changing the timing of registry of the unblocked portion of said circumferential port with said support member port, said changing of timing of registry of said unblocked portion of circumferential port with said support member port changing the timing of valve opening, valve opening duration and valve closing.   
     
     
       3. Apparatus in accordance with claim 1 or 2 wherein said means for blocking and unblocking at least one segment of said circumferential intake port in said rotatable valve comprises at least one pivotally mounted member. 
     
     
       4. Apparatus in accordance with claim 1 or 2 wherein said means for blocking and unblocking at least one segment of said circumferential intake port comprises at least one resilient flapper suitably supported and positioned in the body of said rotatable valve to be movable from an installed and blocking position preventing flow of intake charge through said segment to an unblocking position said position permitting flow of intake charge through said segment. 
     
     
       5. Apparatus in accordance with claim 4 wherein at least one end of said flapper is free to move to block or unblock said segments of said circumferential intake port. 
     
     
       6. Apparatus in accordance with claim 4 wherein said flapper comprises two legs, one leg being secured by appropriate means to said rotatable valve body and the other leg being free to move to block or unblock said segments of said circumferential port. 
     
     
       7. Apparatus in accordance with claim 4 where said flapper comprises at least two legs and both legs move to block or unblock said segments of said circumferential port. 
     
     
       8. In a rotary valve adapted to be located between an intake manifold and a cylinder of an internal combustion engine, said valve having a rotating arcuate valve opening; variable valve timing means mounted for rotation with said rotary valve and responsive to the difference in the pressure in said cylinder and said intake manifold across said valve opening to cause said valve opening to vary an arcuate extent in accordance with said difference in pressure across said valve opening. 
     
     
       9. The rotary valve of claim 8 wherein the arcuate extent of said valve opening increases when said difference in pressure decreases. 
     
     
       10. The rotary valve of claim 8 or 9 wherein said variable valve timing means comprises at least one flapper valve mounted in said rotary valve for rotation therewith. 
     
     
       11. The rotary valve of claim 10 wherein one of said flapper valves is mounted adjacent the trailing edge of said arcuate valve opening. 
     
     
       12. The rotary valve of claim 10 wherein a pair of said flapper valves are mounted adjacent the trailing edge of said arcuate valve opening. 
     
     
       13. The rotary valve of claim 10 wherein one of said flapper valves is mounted adjacent the leading edge of said arcuate valve opening. 
     
     
       14. The rotary valve of claim 13 wherein one of said flapper valves is mounted adjacent the trailing edge of said arcuate valve opening. 
     
     
       15. The rotary valve of claim 13 wherein a pair of said flapper valves are mounted adjacent the trailing edge of said arcuate valve opening.